Electric control structure



Nov. 12, 1935. L. M. PERSONS 2,020,618

ELECTRIC CONTROL STRUCTURE Filed Sept. 6, 1932 3 Sheets- Sheet 1 Nov.12, 1935. Y L. M. PERSONS 2,020,618

ELECTRIC CONTROL STRUCTURE I Filed Sept. 6, 1932 3 Sheets-Sheet 2 Nov.m2, m5, L M PERSON 2,020,618

ELECTRI C CONTROL STRUCTURE Filed Sept. 6, 1932 3 Sheets-Sheet 5Patented Nov. 12, T1935 2,020,618

UNITED STATES PATENTOFFlCE ELECTRIC CONTROL STRUCTURE Lawrence M.Persons, Des Moines, Iowa, assignor to Penn Electric Switch 00., DesMoines, Iowa, a corporation oi Iowa Application September 6, 1932,Serial No.-631,892

6 Claims. (01. 60-52) The object of my invention is 'to provide an Withthese and other objects in view my invenelectric control structure whichis simple, durtion consists in the construction, arrangement and ableand comparatively inexpensive to manufaccombination of the various partsof my device, ture. whereby the objects contemplated are attained,

A further object is to provide a control strucas hereinafter more fullyset forth, pointed out in 5 ture electrically operated for the purposeof openmy claims, and illustrated in the accompanying ing a valve oroperating other controlling devices drawings, in which;

whenever energized, said structure upon being de- Figure 1 is a e elvati 01 n tr c e011- energized allowing said valve or other device totrol structure embodying my invention and showreturn to its initialposition, ing it diagrammatically connected with a gas 10 Still afurther object is to provide in combinaburni g furnace.

tion with a controlling device constrained to re- F u 2 s a e a n On ana d scale of main in one position, a means for moving it to an the rightSide O the d e shown in F u e opposite position whenever such means isener- Figure 3 is a vertical sectional view on the line gized and formaintaining the controlling device 3 of Fi ure 1 in such oppositeposition until deenergization of Figure 4 is an electrical d a maticView the means so that the controlling device can then Showing y controlstllletule as pp e to a be returned to its first position because ofbeing r m h at n electric circuit.

onstr i toward such position Figure 5 is a side elevation of a modifiedform Still a further object is to provide a controlling of e invention-20 devi e and m a for moving it frgm one posi- Figure 6 is a verticalsectional view on an ention to another comprising an expansiblepreslarged scale of the v e h w in ure 5. sure chamber in operativeconnection with the Figure 7 is a t al V ew on the line 'l-'| ofcontrolling device and an electrically operated Figure '25 pump forplacing a medium in the pressure cham- F u 8 s a partial sectional viewshowing t e her under pressure, the controlling device being ValveClosing Parts Figure 6 i a fi t P s arranged with stop means so thatwhen it assumes tie!!- a position because of expansion of the pressureigure 9 is an enlarged ec nal-V e 0 the chamber, the pump can continueto operate beline of Figure cause of the slippage of the medium relativethere- Figure 10 is a side elevation of a o ified orm to, so that whenan electric motor is used for of construction in Which the P p is o8-difieroperating the pump, it will then continue to opent vtypeerate aslong as energized, the continuing opera- Figure 11 is a vertical centralsectional view ation being at a relatively lower speed but not throughthe Valve shown in Fi u e 0- stalling the motor. Figure 12 is asectional view on the line I 2- 35 Still a further object is to have thepump force of Figure air into the pressure chamber and to provide onFigure 13 is a sectional view on the line lil3 oil seal in connectionwith the pump which when f Figure a forced back through the pump whenthe motor is Figure 14 is a view mew a similar to the de-energized willthereafter permit air to quickly l r part of Figure 11 sh wi he p rts ina 40 pass through the pump and thus permit the condifferent D trollingdevice to assume its initial position with a n he c m ny drawings. Ihave used snap action. the reference numeral I to indicate a valve Stilla further object is to provide a conneceasing- The Valve easing has a nlt I! and tion between an oil pump and a valve to be opened an Outlet TheValve is adapted to e 45 thereby, which includes a movable memberautothe flow of gas through a P pe l e 5, alth ugh matically operable topermit by-passing of oil t n be use o Controlling a 01 quid. E from thepressure chamber and around the pump The valve casing ID has therein apartition I when return movement of the valve to closed in which islocated a valve seat 20. A valve disk position occurs. 7 l 22 is adaptedfor coaction with the valve seat 50 Still a. further object is toprovide a. modified 20 and is normally retained in contact thereform ofpump having novel features of construcwith by a spring 24. l tion. Thevalve disk 22 is mounted on a valve stem Still a further object is toprovide a starting 26 slidably mounted in a cover plate 28. Above switchfor the controlling device. thecover plate 28 I provide a pressurechamber 36 through which the valve stem extends. The valve stem issealed relative to the pressure chamber by diaphragms 32 and 34. Thediaphragms are of different effective areas whereby expansnm of thepressure chamber will move the valve disk 22 upwardly against the actionof the spring 24.

Thusfar a normally closed valve has been describedwhich' can be openedby introducing a medium under pressure into the pressure chamber 36 orplacing a medium therein under pressure. In Figure 3, the medium ismerely air. The air can be placed under pressure, or in other words,compressed and for this purpose I provide a pump A operated by anelectric motor B. 1 I I The pump A includes a chamber 36 (see Figure 9wherein the pump shown is the same as the one in Figure 3). Within thechamber 36, a rotor 38 is mounted on an eccentric portion 46 of a motorshaft 42.

. The motor shaft 42 has ends 44 and 46 suitably journalled in bearings.It will be obvious that rotation of the motor shaft 42 will cause a; therotor 36 to wabble within the chamber 36.

In communication with the chamber 36, I provide an inlet 48 and anoutlet 56. The inlet and outlet are sealed relative to each other by ablade 52 secured to the rotor 36 and slidably extending between a pairof oscillating members 54. Rotation of the rotor 36 in the direction ofthe arrow a will pump air, oil, or z'he like from the inlet 48 to theoutlet 56.

The outlet 56 is connected by a stand pipe 56 :and a tube 56 with anintake port 60 of the .,shown being for alternating current in. which avalve to open the valve and when it is fully "the windings 66 only areenergized. The rotor 62 has short circuited windings and the stator 64is of the shaded pole type.

Heretofore it has been customary to provide an electric motormechanically connected with opened, the motor stalls while stillenergized, a spring. or other means being provided to 'return the valveto closed position when the motor is d e-energized. The spring rotatesthe motor backwards usually through a train of geari Such a device hasthe disadvantage of making considerable noise and producing considerableheat in the motor due to the fact that a stalled motor will carry morecurrent than one which is operating. Especially when alternating currentis used, ifoise is produced which is objectionable. I have providedaconstruction, h.ow-

I ever, which operates as follows.

Upon energization of the coils 66, the rotor 62 will rotate foroperating the pump rotor 66. A small quantity of oil 5'! is carried inthe casing of the motor B and at first this oil will be pumped into thestand pipe 56 and thereafter air will be pumped from the motor casingthrough the oil and into the pressure chamber 36 for expanding it. Thisopens the valve disk 22. When spring 24 has been fully compressed, itacts as a positive stop so that the valve cannot be opened any further.The parts of the pump A need not be accurately machined because it isdesirable to have a slight leakage through the parts.

i This is so that when the valve 22 is fully opened,

the rotor 62 will continue to rotate with the air slipping relative tothe pump so that although the pressure in the chamber 36 may be slightlyincreased, the valve will not be opened any further and the electricmotor will simply continue to rotate at a relatively lower speed, suchspeed, 5

pipe 56. 15

At first, the oil 51 will slowly leak through the pump and back to themotor casing. As soon as all the oil has passed the pump, the air willquickly leak through the pump, thereby insuring a snap action for theclosing of the valve my disk 22.

In Figure 1, I have shown how my control device may be connected with agas burning furnace 66. It merely controls the flow of gas through thepipe l6, a suitable pilot light being provided to prevent extinguishmentof the flame. The motor 3 is connected in an electric circuit with aroom theremostat 16 as shown in Figure 4 and a furnace thermostat 12 inthe ordinary manner. temperature lowers to a predetermined degree, themotor will be energized and when the tem peratures rises to apredetermined degree be-,

. cause of operation of the furnace, the motor will be de-energized. Thefurnace thermostat l2 v cuts off the supply of current to the motor B ifthe furnace becomes excessively hot before the room theremostat issatisfied.

In connection with my control device I have shown a startlngswitch Cwhich can be used for initially starting the operation of the controlstructure or starting it after repairs are made.

I have also shown a damper control which can be used in connection withthe furnace 66 if desired. The damper control is merely a rock shaft I4connected by a yoke I6 with the valve stem 26 and by an arm 16 andachain 66-with the draft door 64 of the furnace. Thus when the valve 22is opened, the draft door 64 will be opened this door is left in closedposition.

The starting switch C isassociated with the arm 16 in the followingdescribed manner. The switch 0 is normally open as caused by a latch 66and a spring 66. When it is desired to start the operation of thefurnace, the lever 16 may be swung upwardly for opening the valve 22 andthe latch 66 may then be swung to position under the lever I6 whereafterthe lever 16 may be allowed to raise and the spring 24 will swing thelever down against the shoulder of the latch 88 for holding it in thefull line position of Figure 2.

Thereafter the pump A will again slightly com- 06 press the spring 24,which will release the latch By this arrangement, when the room 30-previous figures and are given the same reference {I numerals with theaddition of the distinguishing characteristic a.

The pressure chamber in this type of valve consists of a cylinder 29 anda piston 3| therein. A considerable quantity of oil 51a is carried inthe housing of the motor B with the rotor 62a operating in the oil. Itis necessary to provide a packing 33 in this type of valve. It is heldtight by the spring 24a. The valve disk 22a is carried by a head 23awhich is slidable relative to the valve stem 26a. It is limited in itssliding movement and constrained toward one position by a spring 25. Thepurpose of this construction is to provide snap action which is lackingbecause oil is used instead of an air with oil seal arrangement as inthe first three figures of the drawings.

The operation of the valve disk 22a from open position in Figure 6 tothe closed position in Figure 8 is first; slow closing of the valve disk22a until slightly spaced from the seat 20a, whereupon the gas pressurein the inlet I2a will act upon the valve disk to quickly close itagainst the tension of the spring 25. This is illustrated in Figure 8.In opening the valve, it will first be slowly opened until the tensionof the spring 25 can overcome the pressure of the gas on the valve disk,whereupon the disk will be quickly opened by the spring 25 and will thenassume the position of Figure 6.

It will be noted that a housing 35 is provided overthe spring 24a. Anyoil leaking past the piston 3| will enter this housing and can return tothe housing of the motor B through a passageway .37.

In this type of valve, the rock shaft 14a must necessarily be packed asindicated at I5. I have provided an electric motor operated controllingdevice in which a motor can continue to operate as long as it isenergized instead of being stalled when the controlling device assumesother than initial position as caused by operation of the electricmotor. Continuing-the rotation of the motor as long as it is energizedtakes less current than when the motor is stalled and there is lessstrain on the physical parts of the device. All of this is possiblebecause of the slippage of the oil or air relative to the pump and thissame slippage feature permits closing of the valve without the necessityof the closing spring having to be strong enough to rotate the motorreversely after it is de-energized.

In Figures 10 'to 14 inclusive, I have shown a modified form of pumpconstruction and an automatically operable member effective to by-passoil from the pressure chamber to the reservoir of the controlling deviceinstead of letting it flow back through the pump. Parts in these figurescorresponding to parts of the previous figures are given the samereference numerals with the addition of the character b.

The pump comprises a casing 92 which, as illustrated on the drawings,forms an end plate for the motor B. The casing 92 is in the form of adisk and has cylinder bores94 extending radially in the form of a cross,as best shown in Figure 12.

A crank shaft bore is indicated at 95. The heads of the cylinders 94extend toward each other and communicate with the bore 95 by means ofpassageways 96.

Within each cylinder 94, is a piston 98 and each piston has a pin Iextending therefrom. The pin I00 extends through a slot I02 of thecasing92.

A crank shaft I04 extends through the bore 85 and has a crank pin I06thereon. A pair of disks I08 are rotatable on the pin I 06 and are eachrigidly connected with a connecting rod I I0 aided by brazing or thelike indicated at I I I. The connecting rod IIO is pivoted to one of thepins I00, while three other connecting rods I I2 are each pivoted to thepair of disks I08 and to the three remaining pins I00.

An intake H4 is provided in the casing 92 and an outlet depression II 6is provided between the 10 disk I08 next to. the casing 92 and thecasing itself.

Depressions I I8 and I 20 are milled in the crank shaft I04 to serve asintake and exhaust ports, respectively. These ports are opposite eachother and arranged with respect to the pistons 98 so that the oil can betaken into one cylinder and discharged from the opposite cylinder duringrotation of the motor armature. There are, accordingly, four intakestrokes and four outlet strokes per revolution of the crank shaft I04.

The outlet passageway III communicates at one end with the outlet spaceH6 and at its other end with the pressure chamber orcylinder I vide abore I22 in which a member I24 is movable. As shown in Figure 11, thismember in one position closes a by-pass opening I26. The member I24 hasa check valve I28 therein opening toward the pressure cylinder 29?).When the oil begins to flow from the pump to the pressure cylinder, thecheck valve I28 is held closed by its spring so that the member I24moves bodily toward the left to block up the opening I26. Thereafter thepressure of the oil will open the 3 check valve and the oil will'then bepermitted to flow into the cylinder 29b.

The member I24 prevents the necessity of allowing the oil upon thereturn stroke, as caused by expansion of the spring 2412 after the motoris 40 de-energized, from passing through the pump. This is accomplishedby the operation shown in Figure 14 wherein the member I24 is shown inits other position. As soon as the oil starts to return, the valve I28will be closed by its spring and the member I24 will be moved bodilytoward the right by the oil, whereupon the by-pass opening I26 will beopened so that the returning oil can pass directly through this openingand into the casing for the motor B. This permits a quicker return ofthe valve to closed position than when the oil has to be forced throughthe slight clear ance spaces provided in the pump.

The member I24 has been illustrated in connection with the specific pumpshown in Figure 11 but can be used with the pump shown in Figure 6equally as well. In either construction it will function the same.

Some changes may be made in the construction and arrangement of theparts of my device without departing from the real spirit and purpose ofmy invention, and it is my intention to cover by my claims, any modifiedforms of structure or use of mechanical equivalents, which may bereasonably included within their scope.

I claim as my invention: v

1. In a control structure, a controlling device movable to oppositepositions, means constraining said device to remain in one of saidpositions and mechanism to move said controlling device to its oppositeposition against such restraint, said mechanism comprising an expansiblepressure chamber, air therein, said expansible pressure chamber being inoperative connection with said controlling device to move it to suchopposite position upon said air being compressed to thereby expand saidpressure chamber, pump and motor. means to compress said air and meansto limit the movement of said controlling device to said oppositeposition, a quantity of oil being provided to seal said pump relative tosaid pressure chamber, said oil being trapped adjacent said pump duringoperation thereof, the means constraining said controlling device toremain in its first mentioned-position serving to contract said pressurechamber and force said oil past said pump and then. allow escape ofcompressed air from the chamber all after saidmotor means ceases tooperate.

2. In a controller, an expansible chamber, a gaseous medium therein, apump for pumping said medium, means for operating said pump, apassageway connecting said pump with said expansible chamber, a trapportion in said passageway and a liquid seal normally filling said pumpbut entering said trap portion when the pump operates, and being held bygravity within the trap portion against the action of said medium,

' While it is being pumped into said expanslble chamber, said mediumbeing so pumped passing through said liquid seal. I

3. In a controller, an expansibie chamber, a gaseous medium therein, apump for pumping said medium, means for operating said pump, apassageway connecting said pump with said on pansible chamber, a trapportion in said passageway and a liquid seal normally filling said pumpbut entering said trap portion when the pump operates, andbeing held bygravity within the trap portion against the action of said. medium,while it is being pumped into said expansible chamber, said medium beingso pumped passing through said liquid seal, said liquid upon the returnof the medium irom said expansible chamber to said pump being firstdriven through the pump by the medium, whereaiter the medium can leakrapidly through thepump for collapsing the expansible chamber.

d. In a controller, an expansible chamber, an air pump, means foroperating said air pump, a passageway connection between said pump andsaid expansible chamber having a trap portion extending upwardly fromsaid pump and a liquid seal-normally filling said pump but entering coldtrap portion when the pump operates and held by gravity within said trapportion against the action or air being pumped into'said expansible l 5chamber, such air being so pumped passing through said liquid. K

5. In a controller, an expansible chamber, an air pump, means foroperating said air pump, a passageway connection between said pump and10 ,said expansible chamber having a trap portion extending upwardlyfrom said pump and a liquid seal normally filling said pump but enteringsaid trap portion when the pump operates and held by gravity within saidtrap portion against the 15 action of air being pumped into. saidexpansible chamber, such air being so pumped passing through saidliquid, said liquid, upon theretiun expansible pressure chamber being inoperative connection with said controlling device to move it to suchopposite position upon said medium being compressed to thereby expandsaid pressure chamber, pump means to compress said 35 medium, a quantityof liquid being provided to seal saidpump relative to said pressurechamber, said liquid being trapped adjacent said pump during operationthereof, the means constraining the controlling device to remain in itsflrstw mentioned position serving to contract said pressure chamber andforce said liquid past said pump and then allow escape of the mediumfrom said chamber, all after said pump ceases to operate.

LAWRENCE M. PERSONS.

